Means for humidifying oxygen



March 9, 1948. J HE|DBR|NK ET AL 2,437,526

MEANS FOR HUMIDIFYING OXYGEN I Filed Oct. 5, 1944 3 Sheets-Sheet l FlgJ.

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MEANS FOR HUMIDIFYING OXYGEN Afforrre March 9, 1948.

J. A. HEIDBRINK ET AL MEANS FOR HUMIDIFYING OXYGEN 3 Sheets-Sheet 3 Filed Oct. 5, 1944 I If,

Patented Mar. 9, 1948 UNITED STATES PATENT OFFICE MEANS FOR HUMIDIFYING OXYGEN Jay A. Heidbrink, Minneapolis, and Clinton G.

Herrick, Hopkins, Minn., assignors to Air Reduction Company, Incorporated, New York, N. Y., a corporation of New York Application October 5, 1944, Serial No. 557,310 3 Claims. (Cl. 261-21) Our invention relates to means for humidifying oxygen as the same is delivered to a nasal catheter in use, and has for its object to provide instrumentalities which will operate in connection with the delivery of oxygen to and through a nasal catheter for completely saturating with water the oxygen as delivered, or even for producing a plus saturation.

Because a nasal catheter necessarily embodies a passage of small diameter, the delivery portion is extended as much as the space in the nasal passage will permit with numerous small side openings, and to get the requisite amount of oxygen it must be delivered under such pressures that jets of oxygen traveling at high velocity will be caused to impinge upon the tissues of the pharynx. The effect of this is to dry out excessively the tissues so impinged producing a condition which induces at the least a grave discomfort to the patient. Yet giving oxygen by a catheter to bedridden patients is often the only practical means or the means considered desirable for the administration of oxygen.

As now practiced, it is cus omary to conduct the oxygen gas, in its travel to the catheter, to the bottom of a body of water held in the container, so the oxygen bubbles up through the water and thereafter passes on to the catheter.

Although this practice effects some degree of humidification, it produces at best only partial saturation of the stream of oxygen delivered through the catheter.

We have discovered that by using oxygen at determined high pressure and deliverin it in a small jet, which, because of the high pressure moves with a, high velocity, and by causing a stream or streams of water to be injected into the path of the jet, and thereafter freeing the moving oxygen from unvaporized water, complete water saturation or even a plus saturation of oxygen received by the patient may be efiected. When so humidified, even though the oxygen jets do strike the tissues with a great deal of speed, there will not be any discomforting drying because the oxygen already carries its maximum absorptive amount of water vapor. Hence, as would be expected, the use of such water-saturated oxygen given by a catheter does not produce injurious or discomforting drying effects in its administration by and through the nasal catheter.

We have also discovered that where a single jet of oxygen is delivered from a high pressure oxygen tank into a tube, at pressures such that the delivery from the catheter produces a jet or oxy- 2 gen of high velocity, 2, degree of vacuum will be produced thereby in the tube or'chamber through which the oxygen passes, and if a stream of water is caused by this vacuum to impinge upon the high velocity oxygen jet, the water will not only be atomized in the tube, but water vapor will be absorbed in the oxygen gas in suificient quantities to completely saturate it.

We also have discovered that if. the water stream across the jet of oxygen be broken into a fine spray, as by being drawn from bubbles in a chamber surrounding but communicating with the vacuum chamber within the jet tube, a higher degree of eiliciency in effecting oxygen humidification is thereby obtained.

Such saturated oxygen gas can then be forced by its pressure in the humidifying chamber to and through the openings in the catheter, where, although impinging upon tissues at high speed, no serious or discomforting drying effect results, because the gas already has absorbed its maximum possible amount of water vapor.

It is a principal object of our invention, therefore, to control the movement of oxygen gas from a tank or other source thereof at high pressure so that the gas will be delivered in a small jet moving at high velocity within a jet tube, a degree of vacuum therein being caused by the moving jet, and to bring a stream of water or water and gas into said tube through the vacuum action therein so that the water will cross the path of the jet, whereby the oxygen gas will be completely saturated with water vapor.

It is a further object of our invention to deliver the jet of oxygen vertically downward into a tube having its open lower end above the surface of water held therebeneath, and to carry a second tube of small internal diameter from toward the bottom of said water to a point at right angles to and immediately adjacent the outer limits of said jet where it is traveling at substantially its highest speed, whereby the vacuum formed in the first tube by the jet will cause water to be drawn up through the second named and small tube so a stream thereof will be thrown across 1 the line of movement of the jet and thereby the water will be finely atomized with a predetermined volume of gas drawn in by the vacuum form a series of openings in the horizontal plane of water delivery across the jet, whereby large volumes of gas are continually drawn into the jet tube along the plane of and about the point of delivery of water across the jet.

It is a further object of our invention to shape the inside of the jet tube with a Venturi opening at the central part and an expanded portion at the upper part and with a multiplicity of openings through the walls of the expanded portion, and to extend a water tube of small bore through the tube wall to a point adjacent the center of the tube, and to control delivery of high pressure oxygen so that a jet thereof is moved at high velocity through the center of said expanded portion and through the venturi and discharged upon a guard plate beyond the open lower end of the jet tube; and to provide a multiplicity of openings of large combined area into the chamber about the jet tube, to cause oxygen to be drawn in through the openings and the whole mixture to be driven upon a guard plate from which it is recirculated again and again, and the gas is completely saturated with water vapor before being forced from the apparatus to the delivery means conveying it to the catheter.

It is a further object of our invention to provide a bell chamber about the vacuum tube, with a small tube connection to near the bottom of the water container, vacuum from the vacuum tube causing water to bubble to a determined level in the bell chamber, and to run a water delivery pipe from below said level to a point close to the gas jet in the vacuum tube.

The full objects and advantages of our invention will now be pointed out in the following detailed specification, and its novel features by which the above noted advantages are attained will be particularly pointed out in the claims.

In the drawings, Fig. 1 is a side elevation view of an embodiment of our invention showing connections therefrom to the oxygen tank and the catheter respectively Fig. 2 indicates somewhat diagrammatically a source of oxygen stored under high pressure adapted to be put'into communication with our humidifying apparatus. Fig. 3 is a sectional elevation view taken on line 2-4 of Fig. 4. Fig. 4 is a sectional plan view taken on line 4-4 of Fig 3. Fig. 5 is a sectional plan view taken on line 5-5 of Fig. 3. Fig. dis a sectional elevation view of a modified form of our invention. Fig. '1 is a sectional plan view taken on line 1-1 of Fig. 6. Fig. 8 is a sectional plan view taken on line 8-8 of Fig. 6.

A cylindrical member H) which may be formed of glass, plastic, or other transparent material. has its top edge contacting a gasket l2 which fits upon a seat l3 inside of an annular outside flange H of a cap piece IS; The lower edge Ii of cylinder lo rests upon an annular gasket II which in turn rests upon a surface of a partition member l8 formed in conjunction with a rim H, the upper part of which surrounds and engages the lower part of cylinder Ill.

The cap piece I! is provided with an internally threaded boss 20. A tube 2|, which will be referred to herein either as a jet tube or a vacuum tube, is formed to provide an upper cylindrical chamber 22, a reduced central Venturi chamber 23 and a-lower expanding chamber 24 which opens from the bottom of the tube at 25. Surrounding the opening 25 is a horizontal flange 23 formed on the tube 2|. The upper end of tube 2| is threaded as indicated at 21 and is screwed into the internally threaded boss 20 to bring the cated upon a gauge 4 upper edge 28 of tube 2| into the space 29 below an annular horizontal surface 30 at the top of threaded opening in boss 20 and surrounding an externally threaded reduced-diameter chamber It follows that with the parts in the position shown in Fig. 2 when the cap piece l5 has its internally threaded boss turned down upon the threaded upper end of tube 2|, the gaskets |2 at the top and I1 at the bottom will be compressed and an upper chamber assembly will result which includes a chamber 32 having for its bottom the partition l8 and a chamber 33 in the cap piece l5, which chambers are sealed from the outside.

Threaded into the reduced portion 3| is an oxygen delivery member 34 which is provided with a central channel 35 extending into a limit port 33 at the center of its bottom, which limit port is of small diameter, and effective at twenty-one thousandths of an inch, which operates satisfactorily over the range of usual delivery through a catheter.

In a plane slightly below the outlet of limit port 36 are a multiplicity of gas inlet openings 31, Fig.. 3, which are adapted to admit oxygen gas to the chamber 22 and within the jet tube 2| when the device is in operation. Also extending through the wall of tube 2| to enter chamber 22 is an end 38 of a small tube 39, which extends through partition I8 to a point near the botton 40 of a water holding chamber 4| forming a cup-shaped member 42 later to be described.

By means of a connector member 43 and fastening nut 44 the chamber 3| and passageway 35 to limit port 36 are connected to a suitable tubing 45. This tubing is in communication with a gas-receiving member 46 which in turn communicates through tubing 41 with an oxygen tank 48, indicated somewhat diagrammatically in Fig. 2. The receiving chamber 46 is connected with a gauge 48 indicating the pressures at which the oxygen will be delivered to the jet port 36. Both the volume of oxygen delivered and the velocity of the jet will of course depend upon the delivery pressure of the gas, as indi- 48, and this pressure will be determined by operation of tank valve 49, indicated diagrammatically at Fig. 2, which is of usual construction.

The oxygen gas forced through jet tube 2| and opening 25 at the bottom thereof, together with the water driven along with it, will be driven upon guard plateau secured to the partition l3 by screws 5|. Spacers 52 hold the guard plate spaced a suitable distance, as indicated at 52, from the lower surface of the partition I8. The guard plate 50 is preferably formed of porous metal or metal having therein a multiplicity of fine perforations, and it acts upon the blast of oxygen gas and water driven upon its upper surface to catch and hold any free water moving with the humidified gas. This gas spreads out in the space 53 and flows up into chamber 32 through a multiplicity of openings 54. These openings have a combined area sufficiently great so that the gas'will move through them at slow speed and chamber 32 any particles of free water.

Part of the gas in chamber 32 will be drawn through openings 31 in jet tube 2| by reason of the considerable degree of vacuum produced by the oxygen jet within the tube and particularly within chamber 22 therein. Thus there will be have no tendency to carry up into a a very considerable recirculation of the oxygen gas from chamber 32. It also follows that since the oxygen being delivered will quickly fill the chamber 32 and any open space within chamber 4|, its pressure will build up to a considerable part of the delivery pressur until the gas will be forced from the chamber 32. It passes through a channel 55 formed in an extension 56 of the cap piece IS. The channel 55 opens at 51 into the chamber 33 in the top of cap piece IS in direct communication with chamber 32. At its other end the channel 55 communicates with a channel 58 through a connector member 59, Fig. 3, which in turn is connected with a tube 60 leading to the catheter 6|, Fig. 1.

The cup-shaped member 42 has a cylindrical wall 62 the upper edges of which are, forced against a gasket 63 held within an annular flange 64 on the bottom of partition l8. This cupshaped member is removably held by a yoke member 65, which has its upper ends 66 and 61 of its side arms provided with screw trunnions 68 and 69 situated in trunnion sockets I and II and held in position by lock nuts 12 and I3. A thumb screw 14 is threaded through a boss I in the central part of yoke member 65 and engages with its end 16 a depression 11 in the bottom wall 40 of cup member 42.

This arrangement enables the cup member 42 to be easily removed and replaced. The chamber 4| is designed to hold a suitable supply of water, and no other means of filling this chamber is provided except to remove the cup. It follows that an excess amount of water can not be introduced into the system. Furthermore, any level of water which is provided by attachment of the normally filled cup 42 to the entire apparatus would be immediately lowered by drawing up of water through the tube 39 by reason of the vacuum formed in the chambers within the jet tube 2| so that the maximum level of water in chamber 4| could not be higher than that indicated at 18 in Fig. 3.

The tube 39 has its bottom 19 adjacent the bottom 40 of chamber 4|. The vacuum in chamber 22 and the other chambers of jet tube 2| will cause water to flow through this tube, be atomized and vaporized in the chambers of the jet tube and to continually circulate until the level of the water in chamber 4| approaches or reaches the bottom 19 of tube 39, when the cup member 42 must be removed and a fresh supply of water provided.

In the modified form shown in Figs. 6, 7 and 8, in place of the Venturi vacuum tube 2| within chamber 32 we provide a simple tube 80 connected in the apparatus otherwise exactly as tube 2|. Upon partition I8 is formed an annular flange 8| which surrounds the bottomrof a bellshaped member 82 in chamber 32. This member surrounds at 83 the threaded upper end 84 of the tube and engages with its lower annular face 85 a gasket 86 resting on the partition I8 inside of flange 8|, thus forming a second chamber 81. Openings 88 are formed through the partition I8 into-the chamber 81, these openings being proportioned in size and number to give a suitable inflow of gas to the interior of tube 80.

Formed in connection with a block 89 is a tube 90, Figs. 6 and 7, which discharges at 9| directly across the line of the gas jet from opening 36. Through block 89 is a passageway 92 which leads into the chamber 81 and connects with the tube passage 99. A second opening and passageway 93 turns downwardly and connects with the tube passageway and also with a downwardly-extending tube 94 which terminates at 95 toward the lower part of the chamber 81. A second tube 96 opens through partition |8 into chamber 81 and extends to a point 91 near the bottom of a water chamber 4|.

The effect of the use of these parts is that the gas jet from the gas opening 36 driving across the opening 9| of tube 90 produces a degree of vacuum in tube 90 which at the same time draws gas through opening 92. This produces a degree of vacuum in chamber 81 and draws spray and gas through tube 94. The vacuum in chamber 81 causes water to be drawn through tube 96 and bubbles of gas to pass through openings 88.- The maximum area of openings 88 in relation to water delivery tube 96, to gas inlet 92 and water delivery through tube 90 is such as to cause tube 96 to maintain a bubbling mass of liquid 98 in chamber 81 with a level substantially as indicated at 99 and which will surround the opening 95 of tube 94.

Hence, the gas drawn through tube 94 will carry with it a spray of water which is carried out of opening 9| into the gas Jet from jet opening 36 and which there is atomized and forced downward through the open end of tube 80 upon guard plate 50, resulting very effectively in a complete humidiflcation. This highly humidified gas will in turn, some part of it, be recirculated through openings 88 and chamber 81 with the result that the gas which finally leaves chamber 32 to go to the catheter has an excess humidification such that as the gas warms on its journey to the catheter it will maintain substantially 100% humidiflcation at the point of delivery from the catheter.

As shown in Fig. 6 the bell casing 82 is formed of transparent material such as glass or transparent plastic or the like, and likewise the wall ID will be of transparent material, This permits a view of the bubbling taking place in chamber 81, which has the advantage of informing the operator that the gas is in fact going through.

Level 99 of liquid within the chamber 81, as shown in Fig. 6, is of course not a fixed level, but a boiling mass with bubbles going through from the openings 89 in partition [8. However, the relation between the opening 96, the air inlet opening 92 and the aggregate area of openings 88 is such that bubbling water will rise in chamber 81 to a point above the opening 95 of tube 94. But then theflow of water through the tube 94 and into the jet tube 80 will be such as to maintain the bubbling mass 98 substantially at a constant height.

The advantages of our invention as heretofore indicated grow out of its simplicity of construction and its high efilciency in delivering oxygen to a catheter which is completely saturated with water vapor. One of the important advantages also comes from the fact that the delivery of oxygen itself creates the vacuum which causes water to be drawn through the tube 39 from the supply in the receptacle and said water to be injected from the transversely extended nozzle 38 in a stream directly across the high velocity Jet of oxygen gas, which results in atomizing the water.

Other advantages come from the fact that this atomizlng of water takes place at the center of a. set of streams of gas pouring in from the surrounding chamber to fill the vacuum caused by the Jet, and that these streams or gas cause the 7 entire oxygen content of the superposed chambers in the apparatus to be repeatedly subjected to vaporized water so that the absorption of water vapor ultimately completely saturates the oxygen gas. Indeed, tests tend to show that there is more than 100% saturation of the gas with true water vapor at the temperature within the chamber; so the gas is completely saturated at the somewhat higher temperature of delivery to the patient.

We claim:

1. An apparatus for effecting saturation of oxygen with water vapor as it is delivered to a nasal catheter, comprising a casing, a partition dividing the easing into upper and lower chambers, the lower chamber adapted to hold a supply of water, a jet tube extending through the upper chamber and opening into the lower chamber, a source of oxygen under pressure and means controlling the flow of that oxygen to cause a high velocity jet thereof to be delivered downwardly along the tube, a bell chamber surrounding .the jet tube, a water pipe having a delivery nozzle in the tube adjacent the air jet and having a lateral opening into the bell chamber and having a downwardly turned end toward the parti tion, a second water pipe extending through the partition to a point near the bottom of the lower chamber in the body of water therein, and a multiplicity of apertures through the partition and into the bell chamber so proportioned in aggregate area that the vacuum created in the bell chamber by the jet will cause water to enter the lower part of the bell chamber and bubble about the lower end of the first-named water pipe to be delivered therethrough in a spray across the gas jet.

2. An apparatus for effecting saturation of exygen with water vapor as it is delivered to a nasal flow of oxygen to cause a gas jet to be delivered downwardly within the jet tube and into the water chamber, means on the partition forming a bell chamber surrounding the jet tube above the partition, said partition having. an opening providing communication between the waterholding chamber and the bell chamber, a vertical pipe with an open lower end and a horizontal pipe connected to the first pipe extending into the jet tube, said horizontal pipe having an open end adjacent the gas jet in the jet tube, and having its opposite end open within the bell chamber, and water conveying means extending from the water chamber into the bell chamber, whereby the vacuum formed in the jet tube will be transmitted into the bell chamber to cause water to be drawn thereinto through the conveying means and to cause gas to be drawn through the opening in the partition to bubble through the water and to cause gas and water to be drawn through the pipe and to be injected into and across the oxygen jet whereby the water is atomized and caused to circulate and to vaporize in the oxygen delivered by the jet.

3. An apparatus for effecting saturation of oxygen with water vapor as it is delivered to a nasal catheter, in accordance with claim 2, wherein there is a guard plate supported beneath and in spaced relation to the partition to catch and hold free water and to spread the gas into the upper portion of the water chamber.

JAY A. HEIDBRINK. CLINTON G. HERRICK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 

